| 摘要 |
<p>A liquid crystal device comprises a liquid crystal cell including a layer of ferro electric smectic liquid crystal material contained between two walls bearing electrodes and surface treated to give both an alignment and a surface tilt to liquid crystal molecules. The material adopts a C2 rather than a C1 arrangement by arranging the surface pretilt κ and the ratio of azimuthal to zenithal anchoring energies β/α to give a positive energy difference ΔWs for the liquid crystal director at the surface in the C1 and C2 states. Additionally the provision of a C2 state may be enhanced by allowing the cell to cool from the isotropic phase to a temperature just below a smectic A to chiral smectic phase, then applying a 50 Hz ac voltage in the range typically 0.1 to 5 volts rms. across the liquid crystal layer for about 90 seconds, then allowing the cell to cool to ambient temperature.</p> |
